Democratic presidential candidate Kamala Harris, senator from California, told Axios that the question of a woman of color’s electability is the elephant in the room for her campaign.

Over the last few months, Harris’ campaign has stagnated in the polls, unable to translate some high-profile moments and high name recognition into increased support from primary voters. Part of the problem, Harris speculated, is that it can be difficult for voters to envision a black woman being president when they’ve never seen it before.

“I have started to, perhaps, be more candid talking about what I describe and what I believe to be the elephant in the room about my campaign — electability,” Harris said. “You know, essentially, is America ready for a woman and a woman of color to be president of the United States?”

Axios’ Margaret Telev countered that America was ready for Barack Obama, the first black man, to be president.

“And this conversation happened for him,” Harris retorted. “There is a lack of ability or a difficulty in imagining someone who we have never seen can do a job that has been done 45 times by someone who is not that person.”

Harris went on to tell a story about campaigning for Obama in Iowa during the 2008 primary. She visited a primarily black senior citizen home and spoke to a woman about voting for Obama. The woman, Harris said, replied, “They’re not going to let him win” — her experience in life didn’t allow her to believe that a black man could become president.

That kind of mindset is what Harris believes she and her campaign have to overcome.

Her campaign has other challenges besides perceived electability issues as a black woman, however. After appearing to be a top contender in the early summer, polling easily in double-digits in June and July, Harris has dropped off to now hover around 3 to 6 percent.

It’s a questionable premise that Democratic voters, who seem to place a high value on gender and racial diversity as positive characteristics in political candidates, are wary of Harris because of her race and gender.

Harris has struggled to establish a clear and consistent position on health care, perhaps the biggest issue in the Democratic primary, and overall has not made an affirmative case as to why she would be a better nominee than front-runners like former Vice President Joe Biden, Sen. Elizabeth Warren (D-Mass.), or even South Bend, Indiana, Mayor Pete Buttigieg.